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1.
Influence of Ni Interlayers on the Mechanical Properties of Ti6Al4V/(WC-Co) Friction Welds 总被引:2,自引:0,他引:2
M. Shamanian M. Salehi A. Saatchi T. H. North 《Materials and Manufacturing Processes》2003,18(4):581-598
Ni interlayers were introduced prior to dissimilar friction welding of Ti6Al4V base material to three cemented carbide substrates. The fracture strength of Ti6Al4V/(WC-6 wt% Co) welds were poor and were markedly improved when 20-µm thick Ni interlayers were introduced prior to dissimilar friction welding. These results were only produced when the (WC-6 wt% Co) cermet was electroplated prior to friction welding. When the Ti6Al4V alloy was electroplated prior to friction welding, fractured WC particles and cracking were observed in the (WC-Co) carbide substrate. The fracture strengths of Ti6Al4V/(WC-11 wt% Co) and Ti6Al4V/(WC-24 wt% Co) welds were not improved when 20-µm thick Ni interlayers were introduced prior to friction welding. During mechanical testing, the Ni layer retained at the dissimilar joint interface created a region of weakness. 相似文献
2.
针对一种侧面和一端的成分呈梯度变化的圆柱体电极模型进行了热应力缓和优化设计。模型材料成分是金属Cu和NiFe2O4尖晶石陶瓷。采用混合律定律确定材料组分.性质关系,利用ansys有限元分析软件计算了从300K(零应力状态)升温到1300K时模型表面的热应力,分析了层数n、成分指数p以及锥角θ对模型表面热应力分布的影响。结果表明:层数n主要影响应力曲线的光滑程度,层数增加,曲线变得平滑;成分指数p是热应力缓和设计的关键,指数越小,应力越小;锥角θ的增加也可缓和热应力,但作用不如成分指数。 相似文献
3.
5Cu/(10NiO-NiFe2O4) cermet inert anodes were prepared by cold-pressing and sintering process, and the effect of superheat degree of melting K3AlF6-Na3AlF6-AlF3 on their anticorrosion performance was studied under electrolysis conditions. The results show that, the fluctuation of cell becomes small with increasing of superheat degree, which is helpful to inhibit the formation of cathodic encrustation; the concentration of impurities from inert anode in bath goes up to certain degree, but it is far smaller than those in traditional high-temperature bath. Increasing the superheat degree of melting K3AlF6-Na3AlF6-AlF3 has unconspicuous effect on the contents of impurities in cathodic aluminum. The total mass fractions of Fe, Ni and Cu in aluminum are 15.38% and 15.09% respectively under superheat degree of 95 and 195 ℃. From micro-topography of anode used view, increasing the superheat degree can aggravate corrosion of metal Cu in inert anode, and has negative influence on electrical conductivity of electrode to some extent. 相似文献
4.
5.
研究了不同含量的碳纳米管及0.8%稀土Y对高Ni含量Ti(C,N)基金属陶瓷组织性能的影响.将不同成分的试样分别于1400℃、1410 ℃、1420℃真空烧结,测试抗弯强度、洛氏硬度,观察背散射电子形貌、断口形貌并做能谱分析.结果表明,加入质量分数(下同)为0.8%Y及0.3%~1.0%的碳纳米管时,碳纳米管含量为0.5%的组织较均匀,芯壳结构明显,抗弯强度及硬度均较高. 相似文献
6.
Mechanical Properties of Porous Materials 总被引:1,自引:0,他引:1
Porous materials are commonly found in nature and as industrial materials such as wood, carbon, foams, ceramics and bricks. In order to use them effectively, their mechanical properties must be understood in relation to their micro-structures. This paper studies the mechanical properties of a few common porous materials: carbon rods, ceramics, polymeric foams and bricks. The characterisation of pore structures was performed using a Mercury Porosimeter. Detailed information was obtained on the density, porosity, surface area and pore size distribution. A large number of experiments on either bending or compression were conducted in order to obtain their macro-mechanical properties such as Young's modulus, hardness and strength. Based on the experimental observations, theoretical models were employed to predict the macro-properties from the micromechanics viewpoint. By studying the deformation of pores the global behaviour was calculated. Two simple formulae for the elastic modulus, E, were proposed: for low values of porosity, , E = E0(1 – 2) (1 + 42) where E0 is the elastic modulus when the porosity is zero; for high value of porosity such as for foams E = E0 (1 – )2. The theoretical results agreed well with the experimental ones. The study has provided insights into the mechanical properties of porous materials over a wide range of porosity values. 相似文献
7.
Ti(C,N)基金属陶瓷中η相的组织研究 总被引:3,自引:0,他引:3
研究了Ti(C,N)基金属陶瓷中η相的组织形态和成份.结果指出,η相中存在微裂纹,对金属陶瓷的力学性能有害,η相中可用分子式(Ni,W,Mo)3(Ti,W,Mo)来表示. 相似文献
8.
Mo、Ni含量与Ti(C,N)基金属陶瓷组织和性能之间的关系 总被引:11,自引:5,他引:11
本文研究了Mo、Ni含量对Ti(C,N)基金属陶瓷组织和性能的影响.结果表明,Mo、Ni含量对组织和性能有很大影响,化学成分决定了组织和性能. 相似文献
9.
TiN及WC加入量对Ti(C,N)基金属陶瓷组织与性能的影响 总被引:2,自引:1,他引:2
本文研究了TiN及WC加入量对金属陶瓷组织和性能的影响.结果表明,随TiN加入量的增加,组织细化,WC形成TiC-WC固溶体的临界加入量约为15%,超过15%时将使部分WC以针状或针片状形式存在,使硬度降低. 相似文献
10.